1. Make sure you have the latest version of Desktop Manager installed. It's 4.2 SP2.
2. Download the above file to the PC then install it to the PC by running the file you downloaded.
3. Locate the vendor.xml file and delete it. It's located in c:\program files\common files\research in motion\apploader
4. Plug in BB and Open Desktop Manager. You should be prompted to upgrade.

The process takes about 45 minutes to an hour depending on how much data you have to backup and restore during the process. Once it's done loading the new OS it will reboot (it may do this twice during the entire process.) You will see a white screen with an hourglass for up to 20 minutes at a time while the DM says "waiting for initialization." Don't unplug from the PC & Don't remove the battery unless the spinning hourglass has been there for 30 minutes or more. If the hourglass has been spinning for more than 30 minutes continuously you will need to wipe the device with JL_Cmder (close out of Desktop Manager during this process.) You will then end up with a white screen with small icons and an error code number like 507 or 543.

If you end up with a white screen with small icons and the number 507/543, simply connect to DM again and run application loader again and it should load the OS to the device.

Locate the Blackberry.alx file in the following folder: C:\Program Files\Common Files\Research In Motion\Shared\Loader Files\8100-v4.2.1.96_P2.3.0.78 and replace it with the one below. Then run Desktop Manager and Application Loader again. It will install the extra themes.

Confused here. I just bought the 8100 Pearl from AT&T a few days ago. On the drop down menu, do I select 8100 Smartphone, or AT&T Red? What is the difference, or does it matter? I don't want to mess this thing up.
Thank you!

ok i think it work... it just takes alittle bit longer to load
however i think there's a bug
after i updated to this version the suto lock key pad thing just stopped working.. does this happen to anyone else..?
all blackberry perl has auto key pad lock right...?